Enable 5.1 surround sound

Paatu Cassette can spread ordinary stereo songs across a 5.1 speaker system: vocals from the centre speaker, ambience from the rears and deep bass from the subwoofer. It switches on by itself as soon as your Mac sends 6 channels.

What you need

• An AV receiver or soundbar with 5.1 (or 7.1) speakers
• An HDMI connection from your Mac to the receiver (directly or with an adapter)

Set up your Mac

1. 1Connect the Mac to your receiver over HDMI, and choose the receiver as the sound output (System Settings › Sound › Output).
2. 2Open Audio MIDI Setup (in Applications › Utilities).
3. 3Select the HDMI device in the list on the left and set Format to 6 ch (6 channels).
4. 4Click Configure Speakers…, choose 5.1 Surround and click Done.

Turn it on in Paatu Cassette

1. 1Open the Sound page (the sliders icon in the player bar) and scroll to Surround 5.1.
2. 2It should say 6-channel output detected: stereo is being upmixed to 5.1. The upmix is on by default.
3. 3Click Test speakers to hear a short hiss from each speaker in turn, or click one speaker in the diagram to test just that one.

Fine-tune

• Presets: Music (the default), Movie and Wide Stage.
• Levels: Center (vocals), Surround (rear) and Subwoofer, from −12 to +6 dB.
• If a test sound comes from the wrong speaker, see Fix 5.1 speaker order.

Or let the receiver do it

Many receivers can upmix stereo themselves (Dolby Surround, DTS Neural:X). Switch the upmix off with the switch on the Surround 5.1 card, and the app sends clean stereo. With a networked Sony receiver you can switch modes from the app: see Control your AV receiver.